Parallel quantitation of salt dioctyl sodium sulfosuccinate (DOSS) and fingerprinting analysis of dispersed oil in aqueous samples.

In many jurisdictions, dispersants are included in contingency plans as a viable countermeasure that can help reduce the overall environmental impact of marine oil spills. When used, it is imperative to monitor the progression of dispersant and oil to assess their environmental fate and behaviour. Amphiphilic salt dioctyl sodium sulfosuccinate (DOSS) is the major effective component of the most commonly available dispersants, such as Corexit® EC9500A. Without proper sample preparation, dispersed oil in water samples could interfere with the accurate analysis of DOSS and easily contaminate the LC-MS system. In this work, solid phase extraction (SPE) weak anion exchange (WAX) cartridges were used to separate oil and DOSS in aqueous samples. DOSS was accurately determined by liquid chromatography coupled with a high resolution Orbitrap mass spectrometer (LC-HRMS). Oil fingerprinting analysis was conducted and total petroleum hydrocarbons (TPHs), polycyclic aromatic hydrocarbons (PAHs), and petroleum biomarkers were determined by gas chromatography-flame ionization detection (GC-FID) and mass spectrometry (GC-MS). This SPE-LC/GC-MS method was used for the analysis of oil-dispersant water samples containing a mixture of Corexit® EC9500A and a selection of crude oils and refined petroleum products. Nearly a 100% DOSS recovery was obtained for various oil-surfactant conditions. Parallel quantitation of oils with dispersants was achieved using this method. A portion of the TPH loss was possibly attributed to oil retained by the SPE column. Chemical fingerprints and diagnostic ratios of target compounds in recovered dispersed oil overall remain unchanged compared with those of all studied oils.

Dataset on European diadromous species distributions from 1750 to present time in Europe, North Africa and the Middle East.

EuroDiad version 4.0 is a set of data tables that store information about the presences/absences and population functionality of diadromous species (lampreys and fish) populations in selected catchments in Europe, the Middle East, and North Africa from 1750 to present time. This database contains distribution and life-history trait information for twenty-eight European diadromous species and geomorphological data for each of the selected catchments, though not every species has data for every catchment and time period. EuroDiad was originally created in 2005-2006 (EuroDiad 1.0 and 2.0), and contained data for 196 catchments and two time periods (1851-1950 and 1951-2010). It underwent a major update in 2009-2010 (EuroDiad 3.2) through a validation process by European fisheries experts. Version 3.2 included the addition of 63 small-sized catchments (< 10,000 km2) and an additional time period (1751-1850) for select species and catchments. This database underwent a second validation process in 2019-2020 and was updated to v 4.0, with the primary goal of providing information for a new generation of species distribution models, referred to as hybrid models, which incorporate both habitat suitability and population dynamics within their framework. Secondary objectives of this update were to: (a) incorporate new catchments for which information was provided by additional experts, (b) validate existing information about the presences or absences of diadromous species and categorize their population functionality within a catchment, and (c) perform data hygiene to prepare the database for broad dissemination. Information on the life history, morphology, and phenology of four emblematic species (i.e. eel, salmon, lamprey and shad) were added in this occasion. Data for this update were validated by DiadES project partners (www.diades.eu) and local experts. This update was focused on catchments located in the Atlantic Area for use in the DiadES project. Data were divided by country, and validation was performed for catchments in Ireland, the U.K., Spain, Portugal, and France under the supervision of national organisations in fisheries and environmental management. DiadES project partners were asked to validate geomorphological information for the catchment (location of the outlet, surface area of the drainage basin, length of the main watercourse, elevation at the headwaters), as well as the presences/absences information and population functionality categories for all species already present in EuroDiad for their country. If possible, verification was done for each of the three time periods. Partners were also asked to provide data for any other catchments for which they had access to information on fish population status. EuroDiad 4.0 now stores data for 350 catchments (of which 292 have population functionality records) and three time periods, though the precision of information varies and not every species has information for each time period. This validation process strengthened the usefulness of EuroDiad, which is now updated and available for use by the research community.

Insertion of a mMoshan transposable element in PpLMI1, is associated with the absence or globose phenotype of extrafloral nectaries in peach [Prunus persica (L.) Batsch].

Most commercial peach [Prunus persica (L.) Batsch] cultivars have leaves with extrafloral nectaries (EFNs). Breeders have selected this character over time, as they observed that the eglandular phenotype resulted in high susceptibility to peach powdery mildew, a major disease of peach trees. EFNs are controlled by a Mendelian locus (E), mapped on chromosome 7. However, the genetic factor underlying E was unknown. In order to address this point, we developed a mapping population of 833 individuals derived from the selfing of "Malo Konare", a Bulgarian peach cultivar, heterozygous for the trait. This progeny was used to investigate the E-locus region, along with additional resources including peach genomic resequencing data, and 271 individuals from various origins used for validation. High-resolution mapping delimited a 40.6 kbp interval including the E-locus and four genes. Moreover, three double-recombinants allowed identifying Prupe.7G121100, a LMI1-like homeodomain leucine zipper (HD-Zip) transcription factor, as a likely candidate for the trait. By comparing peach genomic resequencing data from individuals with contrasted phenotypes, a MITE-like transposable element of the hAT superfamily (mMoshan) was identified in the third exon of Prupe.7G121100. It was associated with the absence or globose phenotype of EFNs. The insertion of the transposon was positively correlated with enhanced expression of Prupe.7G121100. Furthermore, a PCR marker designed from the sequence-variants, allowed to properly assign the phenotypes of all the individuals studied. These findings provide valuable information on the genetic control of a trait poorly known so far although selected for a long time in peach.

Occurrence, characterization, source, and risk assessment of petroleum-related hydrocarbons in sediments along St. Clair River, Ontario, Canada.

Total petroleum hydrocarbons (TPH), n-alkanes, petroleum biomarkers, and polycyclic aromatic hydrocarbons (PAHs) were analyzed in the sediments collected from the shorelines and bottom of St. Clair River, Ontario, Canada. Most of the sampling sites had low TPH (< 20 µg/g). River bottom sediment usually had higher level of TPHs, total alkanes, total biomarkers, and total PAHs than most of the shoreline ones. Mixed biogenic and petrogenic n-alkanes were present in all the sites. Most sites had trace amounts of petroleum biomarkers. Mixed pyrogenic and petrogenic inputs with the predominant petroleum, have contributed to the detected PAHs at all sampling sites. PAHs detected would not show potential toxicity to benthic organisms in all shoreline sampling sites; however, some light molecular weight PAHs (e.g., phenanthrene, 2-methyl naphthalene, and acenaphthylene) are anticipated to have possible adverse impacts to sediment-dwelling organisms in part of the river bottom sediment.

Occurrence, characterization, and ecological assessment of petroleum-related hydrocarbons on the shoreline of Fraser River Delta, British Columbia, Canada.

The Fraser River Delta is a unique and dynamic region supporting the diverse ecosystems and habitats in the Canadian West Coast. Total petroleum hydrocarbons (TPH), n-alkanes, petroleum biomarkers, and polycyclic aromatic hydrocarbons (PAHs) were analyzed for the intertidal sediments taken from the shorelines of the Delta area, British Columbia, Canada, to establish the baseline background data. Most of the sampling sites had low TPH (< 40 µg/g); only two samples had TPH from 100 to 150 µg/g. Mainly biogenic n-alkanes were present in all sites. Non-detectable to trace amounts of petroleum biomarkers were found at most sites. Mixed pyrogenic and petrogenic inputs contributed to the presence of PAHs at most sites. PAHs are not present in amounts anticipated negative effects to benthic organisms in all sampling sites, except that benzo (a) pyrene (BaP) from the upper intertidal zone (UIZ) of Burnaby Fraser Foreshore Park may have possible adverse biological effects.

Population genomics of apricots unravels domestication history and adaptive events.

Among crop fruit trees, the apricot (Prunus armeniaca) provides an excellent model to study divergence and adaptation processes. Here, we obtain nearly 600 Armeniaca apricot genomes and four high-quality assemblies anchored on genetic maps. Chinese and European apricots form two differentiated gene pools with high genetic diversity, resulting from independent domestication events from distinct wild Central Asian populations, and with subsequent gene flow. A relatively low proportion of the genome is affected by selection. Different genomic regions show footprints of selection in European and Chinese cultivated apricots, despite convergent phenotypic traits, with predicted functions in both groups involved in the perennial life cycle, fruit quality and disease resistance. Selection footprints appear more abundant in European apricots, with a hotspot on chromosome 4, while admixture is more pervasive in Chinese cultivated apricots. Our study provides clues to the biology of selected traits and targets for fruit tree research and breeding.

Application of gas chromatography-high resolution quadrupole time-of-flight mass spectrometry in fingerprinting analysis of polycyclic aromatic sulfur heterocycles.

Polycyclic aromatic sulfur heterocycles (PASHs), as a group of major sulfur-containing compounds, widely occur in crude oil and its refined products. Accurate analyses of these petrochemical components play an important role in monitoring oil quality, forensic source identification, and assessment of environmental impact of an oil spill. PASHs occur at relatively lower abundances in most crude oils and refined petroleum products than their corresponding aromatic hydrocarbons and are co-eluted together with some petroleum hydrocarbons in chromatographic analysis, resulting in high uncertainty for their quantitation. Capillary gas chromatography coupled with a quadrupole time-of-flight mass spectrometry (GC-QTOF-MS) provides high resolution and high mass accuracy, which facilitates discrimination of the delicate mass defects of isobaric compounds with the same nominal mass and external matrix material. In this work, GC-QTOF-MS was applied to analyze bicyclic to pentacyclic PASHs including benzothiophenes, dibenzothiophenes, benzonaphthothiophenes, dinaphthothiophenes and their C1- to C4- alkylated homologues in a number of crude oils, refined petroleum products, and environmental samples. GC-QTOF-MS analysis substantially improved the identification confidence and reduced quantitation uncertainty of PASHs and polycyclic aromatic hydrocarbons (PAHs) by eliminating the interferences presented in nominal mass chromatograms.

An innovative bivariate approach to detect joint temporal trends in environmental conditions: Application to large French rivers and diadromous fish.

Most key life-events of organisms are synchronized by complex interactions of several environmental cues to ensure optimal survival and growth of individuals and their offspring. However, global change is known to affect multiple components of ecosystems and cues at the same time. Therefore, detecting joint trends in covariate time series is a crucial challenge in global change ecology that has rarely been addressed so far. In this context, we designed an innovative combination of kernel density estimations and Mann-Kendall trend tests to detect joint temporal trends in a pair of environmental variables. This methodological framework was tested on >30 years (1976-2019) of water temperature and discharge data for 6 large French rivers (the Garonne, Dordogne, Rhône, Rhine, Loire and Vienne rivers). The implications of such trends in both temperature and discharge for diadromous species key life-cycle processes were then explored by checking if significant bivariate environmental changes occurred during seasons of upstream and downstream migration, and reproductive activities. Results were contrasted between rivers and seasons: many rivers displayed an increase in the number of days with high water temperature and low river discharge, but local discharge regulation measures could have mitigated the trend in discharge. Our findings showed that species migrating or spawning in spring were likely to be strongly impacted by the new environmental conditions in the Garonne, Loire and Rhône rivers, given the marked changes in water temperature and discharge associations detected by our new method. Conditions experienced by fall-running and spawning species have been strongly affected in all the rivers studied. This innovative methodology was implemented in a new R package, ChocR, for application to other environments and ecosystems.

Occurrence, characterization, and ecological assessment of petroleum-related hydrocarbons in intertidal marine sediments of Burrard Inlet, Vancouver, British Columbia, Canada.

Total petroleum hydrocarbons (TPH), n-alkanes, petroleum biomarkers, and polycyclic aromatic hydrocarbons (PAHs) were analyzed in the intertidal sediments of Burrard Inlet, Vancouver, British Columbia, Canada. Most of the sampling sites had low TPH (<40 µg/g). Only 10% of sampling sites, located nearby a harbour and densely populated areas, had relatively high TPH (<260 µg/g). Main biogenic n-alkanes were present in all the sites, except for the main petrogenic input in the sample from the upper intertidal zone (UIZ) of the Maplewood Mudflats. Most sites had trace amounts of petroleum biomarkers. Mixed pyrogenic and petrogenic inputs contributed to PAHs at most sites. PAHs did not show potential toxicity to benthic organisms at most sites; however, possible negative effects from some of the detected PAHs were found for the samples from the UIZs of the Maplewood Mudflats and Labour View Park, and from the lower intertidal zone (LIZ) of Gates Park.

Prioritizing river basins for intensive monitoring and assessment by the US Geological Survey.

The US Geological Survey (USGS) is currently (2020) integrating its water science programs to better address the nation's greatest water resource challenges now and into the future. This integration will rely, in part, on data from 10 or more intensively monitored river basins from across the USA. A team of USGS scientists was convened to develop a systematic, quantitative approach to prioritize candidate basins for this monitoring investment to ensure that, as a group, the 10 basins will support the assessment and forecasting objectives of the major USGS water science programs. Candidate basins were the level-4 hydrologic units (HUC04) with some of the smaller HUC04s being combined; median candidate-basin area is 46,600 km2. Candidate basins for the contiguous United States (CONUS) were grouped into 18 hydrologic regions. Ten geospatial variables representing land use, climate change, water use, water-balance components, streamflow alteration, fire risk, and ecosystem sensitivity were selected to rank candidate basins within each of the 18 hydrologic regions. The two highest ranking candidate basins in each of the 18 regions were identified as finalists for selection as "Integrated Water Science Basins"; final selection will consider input from a variety of stakeholders. The regional framework, with only one basin selected per region, ensures that as a group, the basins represent the range in major drivers of the hydrologic cycle. Ranking within each region, primarily based on anthropogenic stressors of water resources, ensures that settings representing important water-resource challenges for the nation will be studied.

Occurrence and weathering of petroleum hydrocarbons deposited on the shoreline of the North Saskatchewan River from the 2016 Husky oil spill.

Following the 16TAN Husky oil spill along the North Saskatchewan River (NSR), the occurrence and natural attenuation of the petroleum hydrocarbons were assessed by analyzing the littoral zone sediments/oil debris collected from July 2016 to October 2017. Husky oil-free, mixed sediment-Husky oil, and Husky oil debris samples were identified for all the collected samples. Shoreline sediments were contaminated by mixed biogenic, pyrogenic and petrogenic inputs prior to the spill. Oil stranded on the shoreline of NSR was moved or buried due to the very dynamic conditions of the shoreline, or cleaned through a series of cleanup activities after the spill. Most normal alkanes were naturally weathered, whereas most of the branched alkanes and all of the saturated petroleum biomarkers remained. Some lighter molecular weight (e.g., 2 to 3-ring) polycyclic aromatic hydrocarbons (PAHs) were lost rapidly after the spill, whereas sulfur containing components, e.g., dibenzothiophenes and benzonaphthothiiophenes, and those having a heavier molecular weight did not change markedly even 15 months post-spill. Similarly, some light hydrocarbons (e.g.,

Monitoring of polycyclic aromatic hydrocarbon contamination at four oil spill sites using fluorescence spectroscopy coupled with parallel factor-principal component analysis.

Fluorescence spectroscopy analysis of oil and environmental samples collected from four oil spill incidents in Canada-a 2016 pipeline spill into the North Saskatchewan River (NSR), Saskatchewan; a 2015 train derailment in Gogama, Ontario; the 1970 sinking of the SS Arrow ship in Chedabucto Bay, Nova Scotia; and the 1970 sinking of the Irving Whale barge in the Gulf of St. Lawrence-permitted assessment of the PAH content of environmentally weathered samples. A recently developed fluorescence fingerprinting model based on excitation-emission matrix-parallel factor analysis-principal component analysis (EEM-PARAFAC-PCA) was applied to (i) evaluate the intensity of the abundant PAH groups in the samples, (ii) investigate changes in the PAH composition of environmental samples over time due to weathering, and (iii) classify the original spilled oil and environmental samples within the already established classes of the fingerprinting PCA model. The environmental sediment samples collected from the Husky Energy spill site show loss of PAHs occurring over the course of 15 months post-spill. However, the extent of weathering depends on several environmental factors rather than solely the time of weathering, the PAH loss was maximum at 15 months. There was a decrease in the PAH content of the environmental samples of Gogama spill collected 20 months post-spill. Almost all of Gogama environmental sediment samples underwent substantial weathering, making PCA classification impractical. The SS Arrow and Irving Whale samples fell within adjacent PCA groups, as they both had a similar type of spilled oil (Bunker C) with similarity in chemical composition.

Retrotransposon methylation and activity in wild fish (A. anguilla): A matter of size.

Understanding how organisms cope with global change is a major question in many fields of biology. Mainly, understanding the molecular mechanisms supporting rapid phenotypic changes of organisms in response to stress and linking stress-induced molecular events to adaptive or adverse outcomes at the individual or population levels remain a major challenge in evolutionary biology, ecology or ecotoxicology. In this view, the present study aimed to test (i) whether environmental factors, especially pollutants, can trigger changes in the activity of retrotransposons (RTs) in wild fish and (ii) if changes in RT DNA methylation or transcription levels can be linked to modifications at the individual level. RTs are genetic elements that have the ability to replicate and integrate elsewhere in the genome. Although RTs are mainly quiescent during normal development, they can be experimentally activated under life-threatening conditions, affecting the fitness of their host. Wild eels were collected in four sampling sites presenting differing levels of contamination. The methylation level and the transcriptional activity of two RTs and two genes involved in development and cell differentiation were analyzed in fish liver in addition to the determination of fish contaminants levels and diverse growth and morphometric indices. An up-regulation of RTs associated to lower methylation levels and lower growth indices were observed in highly contaminated fish. Our results suggest that RT activation in fish experiencing stress conditions could have both detrimental and beneficial implications, affecting fish growth but promoting resistance to environmental stressors such as pollutants.

Characterization of Nitrogen-Containing Polycyclic Aromatic Heterocycles in Crude Oils and Refined Petroleum Products.

A large amount of polycyclic aromatic hydrocarbons (PAHs) and their heterocyclic analogues (N, S, O) are released to the marine environment from natural oil seeps, oil spills, bilge discharges and input of land-based sources. Many of these compounds are toxic and have a deleterious effect on marine biota. Nitrogen-containing compounds in crude oils are typically present as cyclic compounds such as polycyclic aromatic nitrogen heterocycles (PANHs) and are generally classified into the two categories of nonbasic (N-PANHs) and basic compounds (B-PANHs). Chromatographic analyses of PANHs are easily to be interfered by other oil components without proper sample preparation prior to instrumental analysis. In this work, dual solid phase extraction columns of 3-(isocyanato)propyl-functionalized silica gel (Si-NCO) and silica gel were employed to efficiently separate both N-PANHs and B-PANHs from saturated and aromatic petroleum hydrocarbons, which enable simultaneous accurate analyses of these groups with single sample preparation. Crude oils studied contain various concentrations of N-PANHs including carbazole, benzocarbazole and B-PANHs including quinolone, acridine and benzoacridine as well as their alkylated homologues. These compounds in light fuel and lubricating oil are generally not detected or are only in trace concentration, but have considerable abundance in heavy fuel oils. Crude oils from different sources and various petroleum products have their unique absolute concentrations and relative distribution patterns of PANHs. Chemical fingerprints of PANHs can provide valuable information for forensic oil spill identification and improve the understanding of the fate, behaviour and chemical degradation of spilled crude oil.

Deletion of the miR172 target site in a TOE-type gene is a strong candidate variant for dominant double-flower trait in Rosaceae.

Double flowers with supernumerary petals have been selected by humans for their attractive appearance and commercial value in several ornamental plants, including Prunus persica (peach), a recognized model for Rosaceae genetics and genomics. Despite the relevance of this trait, knowledge of the underlying genes is limited. Of two distinct loci controlling the double-flower phenotype in peach, we focused on the dominant Di2 locus. High-resolution linkage mapping in five segregating progenies delimited Di2 to an interval spanning 150 858 bp and 22 genes, including Prupe.6G242400 encoding an euAP2 transcription factor. Analyzing genomic resequencing data from single- and double-flower accessions, we identified a deletion spanning the binding site for miR172 in Prupe.6G242400 as a candidate variant for the double-flower trait, and we showed transcript expression for both wild-type and deleted alleles. Consistent with the proposed role in controlling petal number, Prupe.6G242400 is expressed in buds at critical times for floral development. The indelDi2 molecular marker designed on this sequence variant co-segregated with the phenotype in 621 progenies, accounting for the dominant inheritance of the Di2 locus. Further corroborating the results in peach, we identified a distinct but similar mutation in the ortholog of Prupe.6G242400 in double-flower roses. Phylogenetic analysis showed that these two genes belong to a TARGET OF EAT (TOE)-type clade not represented in Arabidopsis, indicating a divergence of gene functions between AP2-type and TOE-type factors in Arabidopsis and other species. The identification of orthologous candidate genes for the double-flower phenotype in two important Rosaceae species provides valuable information to understand the genetic control of this trait in other major ornamental plants.

Occurrence, source and ecological assessment of petroleum related hydrocarbons in intertidal marine sediments of the Bay of Fundy, New Brunswick, Canada.

Total petroleum hydrocarbons (TPH), n-alkanes, petroleum-related biomarkers of terpanes and steranes, and polycyclic aromatic hydrocarbons (PAHs) were analyzed in the intertidal sediments in the Bay of Fundy, Nova Scotia/New Brunswick, Canada. Sites close to the harbour and more densely populated areas had higher TPH levels than other pristine areas. n-Alkanes presented a typical single bell-shape in n-C16 to n-C35 range and an obvious odd to even carbon preference. Most sites had trace amounts of petroleum biomarkers. Abundant non-alkylated PAHs and lower amounts of alkylated PAHs represented the major input of the incomplete combustion of solid (e.g., coal, coke, biomass, and coal tar) and liquid fuels. The toxicity estimation for PAHs indicates that they did not have potential toxicity to benthic organisms at most sampling sites. However, possible to probable negative effects from the measured PAH concentrations were found for the two samples from Courtenay Bay and Saint Andrews.

Fate of oxygenated intermediates in solar irradiated diluted bitumen mixed with saltwater.

Two types of diluted bitumen (dilbit) and a light crude oil spiked onto the surface of saltwater were irradiated with natural solar light in Ottawa to assess the impact of sunlight to the fate of oxygenated intermediates. Oxygenated components, including carbonyl polycyclic aromatic hydrocarbons (PAHs) and acidic polar fractions (naphthenic acid fraction compounds, NAFCs), were identified after periods of solar exposure under both winter and summer conditions. Carbonyl PAHs and NAFCs were formed in both seasons; however, light crude and summer irradiation produced higher abundance of them than dilbits and winter exposure. The formed NAFCs were abundant with the congeners containing a heteroatom of oxygen only (Oo species), accompanied by the minor amounts of sulfur- and nitrogen-containing acids. The produced Oo species were predominant with the congeners with light molecular weight, high degree of saturation and heavy oxygen numbers. For both carbonyl PAHs and NAFCs, their abundance continually increased throughout the period of winter exposure. In the summer, some carbonyl PAHs and all Oo species increased during the early exposure period; then they decreased with continued exposure for most oils, illustrating their transitional nature. Oxygenated intermediates thus appear to have been created through the photo-oxidation of non-to medium-polar petroleum hydrocarbons or the intermediates of aldehydes or ketones (O1). Oil properties, the duration of exposure, exposure season and the chemical structure of these intermediates are critical factors controlling their fate through photo-oxidation. The observed chemical changes highlight the effects of sunlight on the potential behavior, fate and impact of spilled oil, with the creation of new resin group compounds and the reduction of aromatics and saturates. These results also imply that the ecological effects of spilled oil, after ageing in sunlight, depend on the specific oil involved and the environmental conditions.

Characterization of chemical fingerprints of unconventional Bakken crude oil.

The ability to characterize the composition of emerging unconventional Bakken tight oil is essential to better prepare for potential spills and to assess associated environmental concerns. The present work measured and compared the physical and chemical properties of Bakken crudes with conventional crude oils from various regions and different types of refined petroleum products. The physicochemical properties of Bakken crude are overall similar to those of conventional light crudes. The Bakken crude consists of high concentrations of monoaromatic hydrocarbons and alkylated PAHs with a clear dominance of the alkylated naphthalene homologues followed by the phenanthrene series. Its pyrogenic index (PI) values are considerably lower than typical conventional crude oils. The Bakken crude oils in this study exhibit a low abundance of petroleum biomarker such as terpanes, steranes and diamondoids and bicyclic sesquiterpanes. Since tight oil from the Bakken region is produced from low-permeability formations, variations in abundance and diagnostic ratios of common target petroleum hydrocarbons were found among these oils.

Integrated QTL detection for key breeding traits in multiple peach progenies.

BACKGROUND: Peach (Prunus persica (L.) Batsch) is a major temperate fruit crop with an intense breeding activity. Breeding is facilitated by knowledge of the inheritance of the key traits that are often of a quantitative nature. QTLs have traditionally been studied using the phenotype of a single progeny (usually a full-sib progeny) and the correlation with a set of markers covering its genome. This approach has allowed the identification of various genes and QTLs but is limited by the small numbers of individuals used and by the narrow transect of the variability analyzed. In this article we propose the use of a multi-progeny mapping strategy that used pedigree information and Bayesian approaches that supports a more precise and complete survey of the available genetic variability. RESULTS: Seven key agronomic characters (data from 1 to 3 years) were analyzed in 18 progenies from crosses between occidental commercial genotypes and various exotic lines including accessions of other Prunus species. A total of 1467 plants from these progenies were genotyped with a 9 k SNP array. Forty-seven QTLs were identified, 22 coinciding with major genes and QTLs that have been consistently found in the same populations when studied individually and 25 were new. A substantial part of the QTLs observed (47%) would not have been detected in crosses between only commercial materials, showing the high value of exotic lines as a source of novel alleles for the commercial gene pool. Our strategy also provided estimations on the narrow sense heritability of each character, and the estimation of the QTL genotypes of each parent for the different QTLs and their breeding value. CONCLUSIONS: The integrated strategy used provides a broader and more accurate picture of the variability available for peach breeding with the identification of many new QTLs, information on the sources of the alleles of interest and the breeding values of the potential donors of such valuable alleles. These results are first-hand information for breeders and a step forward towards the implementation of DNA-informed strategies to facilitate selection of new cultivars with improved productivity and quality.